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Antenna Measurement Facilities

I have designed and built many of the rectangular and tapered anechoic chambers in South Africa with operating frequency ranges typically from 0.5 to 40 GHz, for example there are two tapered anechoic chambers at SAAB EDS.† The microwave test range of the National Antenna Test Range (NATR) at Paardefontein (north of Pretoria) was designed and implemented by me in the late 1970s and early 1980s.† This is a 500 m ground reflection antenna test range covering from below 300 kHz to 40 GHz.† It is rated as one of the best facilities of its type in the world.† The facility was originally designed for the measurement of radar antennas but was subsequently adapted for MF/HF and VHF/UHF frequencies as well.† In 2007, I devised three custom measurement set ups at the NATR to calibrate and measure a† high accuracy communications intelligence (COMINT) direction finding (DF) and omni-directional monitoring antenna system operating over the HF/VHF/UHF frequency ranges for submarine applications. Of primary concern was to have a test set up with a high level of repeatability since customer measurements were to be made at times separated by many months. This NATR and its capabilities can be viewed here.

During 2006/2007, for an international customer, I completed the detailed electrical and mechanical designs, installation and commissioning of a state-of-the-art tapered anechoic chamber (4.3 m x 4.3 m x 17.4 m) operating over the 200 MHz to 40 GHz frequency range. All test equipment and peripherals had to be specified by me and the customerís personnel were trained on site in the operation and use of the tapered anechoic chamber. This anechoic chamber has outstanding performance over the entire frequency range.

In May 2014, I completed the installation of a tapered anechoic chamber (2.8 m x 2.8 m x 10.4 m) for a local antenna company. The electrical design, absorber specification and lists of peripheral equipment were done by me. The local company used its own in-house resources for the manufacture of the chamber shell and also installed the microwave absorbers under my supervision. This anechoic chamber can operate from 300 MHz to 40 GHz with the appropriate test equipment.